In a blender, liquefy the beets, carrots, celery, parsley, onion and garlic with some of the tomatoes and the juice they are canned in. When this is a pretty smooth puree, put it into a pot and add the rest of the tomatoes and bring it to a gentle boil. Reduce heat and simmer for a ten minutes. Add mushrooms and simmer for about 1/2 hour. Add green pepper. Season with salt, pepper and basil as desired. Allow it to simmer a little longer, while you cook the pasta. Serve hot with a big smile.